Tentative skid-resistance requirements for main rural highways = Versuch der Festlegung von Anforderungen an die Griffigkeit von Hauptverkehrsstrassen ausserhalb von Ortschaften.

The principal friction components are described and the adhesion coefficient and hysteresis coefficient are analysed. A difference is made between the skidding tire and the slipping tire. Tire operating modes are mentioned, together with factors which affect pavement friction and surface classifications. Finally minimum skid- resistance requirements are described.